Dynamic sea clutter simulation at low grazing angles

Download
index.pdf
2018
Erdoğan, Muhammed Z
Show full item record
308
views
125
downloads
High-amplitude clutter signals may be observed during radar operation due to environmental objects having large surface areas. By Doppler processing, modern radars can discriminate between echoes from mobile targets and echoes from stationary objects like mountains, buildings and so on. However, there is no simple way to do this discrimination for sea clutter since sea is always on the move. Therefore, statistical and empirical models are frequently used to characterize sea clutter. Yet, such models are unlikely to predict sea clutter accurately, particularly in complex sea conditions. In this thesis, we approach this issue in a different way. Dynamic simulation of sea clutter is performed to obtain more accurate results. In this simulation, sea surface is modeled depending on time-varying environmental factors, like sea wave height. Therefore, change of clutter is compatible with temporal and spatial correlation of sea surface. Then, a model is suggested to mimic realistic sea clutter parameters like normalized radar cross sections and Doppler frequency shifts. By applying the suggested model to the generated sea surface in certain time periods, complex radar data matrix is constructed. Finally, the simulation results are analyzed and compared to some of the available experimental data for different scenarios, and good agreement is observed.
Radar cross sections., Doppler effect., Moving target indicator radar., Signal processing., Sound-waves.
http://etd.lib.metu.edu.tr/upload/12621879/index.pdf
https://hdl.handle.net/11511/27097
Graduate School of Natural and Applied Sciences, Thesis

Suggestions

Parametric estimation of clutter autocorrelation matrix for ground moving target indication
Kalender, Emre; Tanık, Yalçın; Department of Electrical and Electronics Engineering (2013)
In airborne radar systems with Ground Moving Target Indication (GMTI) mode, it is desired to detect the presence of targets in the interference consisting of noise, ground clutter, and jamming signals. These interference components usually mask the target return signal, such that the detection requires suppression of the interference signals. Space-time adaptive processing is a widely used interference suppression technique which uses temporal and spatial information to eliminate the effects of clutter and ...
Optimization of vibration characteristics of a radar antenna structure
Baran, İsmet; Özgen, Gökhan Osman; Ciğeroğlu, Ender; Department of Mechanical Engineering (2011)
Radar antenna structures especially array antennas which are integrated onto structures of aerial vehicles are subject to dynamic structural and aerodynamic loads. Due to occurrences of these dynamic loads there will be certain dynamic deformations which affect the antenna’s performance in an adverse manner. The influence of deformations and vibrations are important on array antenna structures, since they cause a change in orientation of elements of the phased array antenna which affects the gain of the ant...
Efficient Methods of Doppler Processing for Coexisting Land and Weather Clutter
Candan, Çağatay; Yılmaz, Ali Özgür (2008-05-30)
The joint suppression of returns from land and weather clutter is required in many radar applications. Although the optimal method of land-weather clutter suppression is known, the solution is usually not practical to implement. In this paper, we propose a method that employs rank-1 and rank-2 approximations on the weather clutter correlation matrix to obtain suboptimal but simpler detectors which are easier to implement. The performance of the proposed detectors is compared with the optimal detector and so...
Low elevation target detection and direction finding
Uyar, Görkem; Tanık, Yalçın; Kuzuoğlu, Mustafa; Department of Electrical and Electronics Engineering (2012)
Ground based radars often experience difficulties in target detection and direction finding (DF) applications due to the interference between the direct and surface reflected signals when the targets fly at low altitudes. In this thesis, the phenomena governing the low angle propagation are overviewed and a multipath signal model including the effects of refraction, specular reflection, diffuse reflection, curvature of the earth and antenna polarization is presented. Then, the model is utilized to develop d...
Spectral and statistical analyses of experimental radar clutter data
Kahyaoğlu, Nazlı Deniz; Yılmaz, Ali Özgür; Department of Electrical and Electronics Engineering (2010)
The performance of radar detection and imaging systems strongly depends on the characteristics of radar clutter. In order to improve the radar signal processing algorithms, successful analysis and modeling of radar clutter are required. For a successful model of radar clutter, both the spectral and statistical characteristics of the clutter should be revealed. Within the scope of this study, an experimental radar data acquisition system is established to analyze radar clutter. The hardware and the data proc...
Citation Formats
M. Z. Erdoğan, “Dynamic sea clutter simulation at low grazing angles,” M.S. - Master of Science, Middle East Technical University, 2018.
METU IIS - Integrated Information Service open@metu.edu.tr